class Students_system():
    name = []
    secrect_information = {}
    information = []

    def welcome(cls):
        print('''Welcome to 学生操作系统V1版本
        查询操作请按1
        插入操作请按2
        删除操作请按3
        修改操作请按4
        list\'s information 指令:list
        退出信息操作界面输入:goout
        退出系统请输入over
        ''')

    def __init__(self,sid,name,age,gander):
        self.sid = sid
        self.name = name
        self.age = age
        self.gander = gander


